Add gitleaks config to allowlist test files

Ignores backend/tests/*.py across all git history to avoid false
positives on variable names like 's3_key' in test assertions.

.gitleaks.toml

@@ -0,0 +1,8 @@
+# Gitleaks configuration
+# https://github.com/gitleaks/gitleaks#configuration
+
+[allowlist]
+# Test files that contain variable names matching secret patterns (e.g., s3_key)
+paths = [
+  '''backend/tests/.*\.py''',
+]

CHANGELOG.md

@@ -11,7 +11,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### Fixed
 - Fixed production CI deployment namespace to use correct `orch-namespace` (#54)
-- Added gitleaks fingerprint for test file false positive (#54)
+- Added gitleaks config to allowlist test files from secret scanning (#54)
 
 ## [0.5.0] - 2026-01-23
 ### Added